Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Existing Beam: Repair or O.K.?

[Subject Prev][Subject Next][Thread Prev][Thread Next]
I feel vastly less qualified than most of this list to offer any kind
of recommendation.

Still, if I had to make a change, it would be the 3rd option, because
the strength of those PSL's is entirely a known quantity.  Option 2
would scare me because you just don't have any way of knowing how
you're changing the dynamics.  Option 1 would make your lawyer the
happiest (outside my scope of work!) but might make it hard to sleep
at night...

Chris

On Sun, Apr 13, 2008 at 1:10 PM, Bill Allen <T.W.Allen(--nospam--at)cox.net> wrote:
>
>
>
>
> I'm working on a small commercial remodel in Southern California. The part
> of the work for which I'm responsible is nearly complete. However, when the
> inspector came out to finalize the framing, he noticed problems in an
> existing beam which is not part of my original scope of work. The building
> is three stories and is rectangular. There is a beam line running down the
> middle of the long direction. For my work, I had to remove and replace the
> existing beam where the office is being remodeled. Beyond my work, the
> existing beam is unmodified. What caught the inspector's eye are small holes
> drilled in the beam used to pass electrical conduit. I haven't run the
> numbers yet, but I believe these holes are O.K. What is troubling is that,
> on one span, there is a long crack down the wide face of the beam for most
> of the length. Worse yet, it appears that the beam above the crack has
> rotated slightly. Below is a sketch prepared by my original CAD program.
> I've exaggerated the rotation, but it is obvious. The beam is huge. It's
> 18-3/4"x701/4". It spans about 12-1/2 feet and supports two floors and a
> roof. I'm concerned about two things; the ability of the beam to transfer
> VQ/I stresses through the cracked region and the ability of the beam to
> remain stable if the crack propagates. Maybe there are other things I should
> worry about. There are three methods of addressing this problem that I can
> think about off the top of my head and they are:
>
> 1.      Do nothing; the beam is still structurally viable.
>
> 2.      Add Simpson LTP4s at 12" o.c. or so which would stitch the crack in
> the hopes that it will keep the crack from enlarging/propagating and will
> hopefully transfer the VQ/I stresses by an unknown load transfer path.
>
> 3.      Don't mess around with it and repair the beam by sandwiching two
> PSLs, one on each side and designed to take 100% of the load. I would have
> the contractor jack the beam as far as he can (there are bearing walls
> above) before he bolted these beams to the existing beam. If I could get
> 100% of the load off the existing beam, it would then act to only transfer
> the load to the PSLs.
>
>
>
> What would you do and why?
>
>
>
> TIA,
>
>
>
>  T. William (Bill) Allen, S.E.
>
> ALLEN DESIGNS
>
> Consulting Structural Engineers
>   V (949) 248-8588 • F(949) 209-2509
>
>
>
>
>
>
>
>

******* ****** ******* ******** ******* ******* ******* ***
*   Read list FAQ at: http://www.seaint.org/list_FAQ.asp
* 
*   This email was sent to you via Structural Engineers 
*   Association of Southern California (SEAOSC) server. To 
*   subscribe (no fee) or UnSubscribe, please go to:
*
*   http://www.seaint.org/sealist1.asp
*
*   Questions to seaint-ad(--nospam--at)seaint.org. Remember, any email you 
*   send to the list is public domain and may be re-posted 
*   without your permission. Make sure you visit our web 
*   site at: http://www.seaint.org 
******* ****** ****** ****** ******* ****** ****** ********